Rock-uplift history of the Central Pontides from river-profile inversions and implications for the evolution of the North Anatolian Fault

Major strike-slip fault systems on Earth, like the North Anatolian Fault (NAF), play an important role in accommodating plate motion, but little is known about their spatiotemporal evolution. In the Central Pontides, north of the central segment of the NAF, data from thermochronology suggest an exhumation phase occurred after 11 Myr. However, the precise onset of this uplift phase is poorly constrained. In this study, we define the spatiotemporal rock-uplift pattern within the Central Pontides over the last ~10 Myr by performing linear inversions of 19 river profiles draining the northern margin of the Central Pontides, from the Sinop Range to the Black Sea. We use 21 new ¹⁰Be-derived basin-average denudation rates to calibrate an erodibility parameter, necessary to infer rock-uplift histories from χ-transformed river profiles. Our results document an increase in rock-uplift rates after 10 Ma, with peaks of 0.15–0.25 km/Myr occurring between 4 and 2 Ma. Moreover, the spatiotemporal uplift variations suggest that rock uplift migrated westward over a period of 2–2.5 Myr. Linking the uplift to the transpression produced along the NAF central segment, we used the faster uplift onset to calculate the NAF propagation rate, estimated to be ~74±13 km/Myr. Combining our results with those from previous studies on the NAF age, we found differences in fault-propagation rates that coincide with differences in the orientation of the NAF relative to plate-convergence vectors. Fault segments with higher obliquity appear to have propagated at rates up to 2-fold slower than those oriented parallel to the plate-convergence vector.